#define _CRT_SECURE_NO_WARNINGS


#include<stdio.h>

int find_min();

int main()
{
	int k = 0;
	scanf("%d", &k);
	int num = find_min(k);
	printf("%d", num);

	return 0;
}

int find_min(int k)
{
	int n = 1;
	double sum = 0.0;

	do
	{
		sum += 1.0 / n;
		n++;
	} while (sum <= k);

	return n - 1;
}